An apparatus for conveying preforms is disclosed in U.S. Pat. No. 4,382,760. In this prior specification, there is disclosed a pick-up chain, which receives preforms to be heated which are supplied thereto in a generally vertically downward direction. The preforms are received in circular openings which are not adjustable in respect of their diameter. By means of the chain, the blanks are then conveyed through a stretching and blowing machine.
Such a known arrangement has the disadvantage that it can only be used to produce containers or bottles of one specific size. This is because only blanks having a specific diameter fit into the receiver means, that is to say, the openings in the chain, for conveyance through the heating arrangement.